Companion planting guide
It’s a beautiful thing to watch bees buzzing around cornflowers and thyme before pollinating your fruit and vegetables, white butterfly caterpillars feasting on nasturtiums rather than your brassicas, and neat rows of leeks, carrots and lettuce all thriving alongside each other.
It turns out that nature has its own advice for gardening, and while the rules are not always hard and fast, experimenting with a few of them could help your garden flourish, relatively pest and disease free, with reduced use of chemicals.
The philosophy is known as companion planting. For the uninitiated it can seem a daunting prospect requiring a degree in horticulture to decipher all tables, charts and lists available on the internet. But an easy way to think of companion planting is the grouping together of plants in a way that helps them grow better.
Companion planting can work in any size garden with companions generally falling into three different categories. Those plants that deter pests such as white butterflies and aphids or give them something other than your brassicas to chew on, those that fix nitrogen in the soil and those that attract beneficial insects such as hover flies, honey bees and ladybirds.
Here are a few basics to get you started:
First get rid of weeds. Weeds are often reservoirs of pests and diseases and if you remove them then you can choose which plants to grow together for the benefit of your fruit, vegetables and flowers.
Even the smallest vegetable garden will benefit from some flowers grown amongst the vegetables. Let nasturtiums trail through your patch. Aphids, whiteflies and white butterfly caterpillars will feed on them in preference to your vegetables, the bonus being the tender young leaves and flowers of nasturtiums make a peppery addition to your salads. And dot a few marigolds in the corners of your patch or alongside your tomatoes to help deter pests with their scent and add a cornflower or two as beneficial insects, including bees, love the blue flowers.
Basil, thyme, rosemary, dill and parsley are all great additions to your garden. Herbs are expensive to buy from the supermarket but easy to grow from seed and bees love them when they’re in flower. Plant basil alongside your tomatoes, it is said to improve the yield and flavour. You can quickly pick the two together for an amazing bruschetta topping. Try planting a few herbs alongside your brassicas (broccoli, cabbage, cauliflower, brussels sprouts, kale, etc.) as they repel white butterfly.
Peas, Beans, Squash and Corn
If you are looking to save a bit of space, plant corn, squash and peas or beans together. They get on well and you can let the peas and beans climb up the corn stalks. This combination is known as the Three Sisters and was a method used by Native Americans. Just keep them away from garlic or onions. Peas and beans also grow relatively quickly from seed making them economical to grow and bacteria in their root nodules fix nitrogen from the air, naturally fertilising the soil and enriching your garden.
Zucchini and Cucumber
Plant zucchini and/or cucumber alongside your corn at the front of your raised garden and let them spill over the sides. Just keep it away from your potatoes.
There are so many varieties of lettuce now and they’re superfast to grow from seed. Plant them under your tomatoes and alongside your basil to offer them a bit of shade and pick off leaves as they grow for your salads rather than pulling out the whole plant.
Leeks, Carrots, Radishes, Onions, Spinach and Beetroot
Leeks and carrots are particularly happy companions, the leeks helping to repel carrot rust fly. Grow them in alternate rows. They will also grow well alongside lettuces, radishes, onions, spinach and beetroot. Beetroot also does well when planted alongside your brassicas; plant a few beetroot seeds around your broccoli or cauliflowers, they don’t need a lot of sun and will grow in shade. You can also scatter your onions throughout your garden as they deter aphids but keep them away from your peas and beans.
Tomatoes, Peppers, Chillies and Eggplants
These plants all do well together as they are all heat lovers, so make sure you leave enough space so they’re not shading each other. With the basil alongside you have the base of a delicious parmigiana. However, keep your tomatoes well away from potatoes, strawberries and fennel. Fennel is best planted in isolation as it does not help many other plants.
Potatoes do well beside corn, spinach, peas, beans and cabbages. Just don’t plant them beside tomatoes, pumpkins, melons or cucumbers. You can also plant them to the side of your garden in large bags or bins, topping up their green foliage with soil as it continues to grow towards the surface. This saves space and a lot of digging; once they have grown, just remove layers of soil to reveal your potatoes for dinner.
Melons will happily scramble through your garden, but they do need a lot of space so they are best planted around the edges of your patch. They get along with most other plants but keep them away from your potatoes.
Overall, go for diversity in your garden rather than neat rows of vegetables. It is fun to experiment as the ‘rules’ are not hard and fast, they are simply guides. Intersperse herbs and flowers to attract or detract insects and combine fast growing plants with those that are slower or like a bit of shade. When it comes time to harvest the result will also feel more like foraging for your dinner.
Download our handy McGregor's guide to companion planting....Companion Planting Guide.pdf22 February 2024